OBJECTIVETo explore the inhibition pathway of the EBV-immortalized cells (CD23(+)) in children with infectious mononucleosis (IM) caused by Epstein-Barr virus.

METHODSThe expressions of CD23, CD19, CD95, Bcl-2 and the co-expressions of CD23CD95, CD19CD23 on peripheral blood mononuclear cell (PBMC) were analyzed by flow cytometry (FCM) during acute phase, early convalescent phase and convalescent phase of 34 EBV-IM children and compared with that of 24 healthy donors.

RESULTS(1) The levels of CD23(+) and CD23(+)CD19(+) cells decreased and CD95(+), CD95(+)CD23(+), Bcl-2(+) cells increased markedly in IM patients in acute phase [CD95(+) cells (19.43 +/- 8.46)%; CD95(+)CD23(+) cells (1.81 +/- 1.71)%; Bcl-2(+) cells (23.41 +/- 26.47)%] and early convalescent phase [CD95(+) cells (12.94 +/- 5.05)%; CD95(+)CD23(+) (1.05 +/- 1.20)%; Bcl-2(+) cells (10.54 +/- 9.68)%], as compared with those of healthy controls [CD95(+) cells (10.39 +/- 2.90)%; CD95(+)CD23(+) cells (0.50 +/- 0.46)%; Bcl-2(+) cells (7.25 +/- 2.88)%]. The earlier the course of IM, the more abnormal the expressive levels. All the abnormal results returned to normal in convalescent phase. (2) Positive relationships were observed between the expressions of CD95(+)CD23(+) cells and that of CD23(+) cells, CD23(+)CD19(+) cells during acute and early convalescent phase, the expressions of Bcl-2(+), CD3(+) cells and CD23(+), CD23(+)CD19(+) cells during acute phase, the expressions of CD95(+)CD23(+) cells and Bcl-2(+) cells during acute phase, and the expressions of CD95(+)CD23(+) cells and CD95(+) cells during convalescent phase.

CONCLUSIONThe results indicate that CD95L-CD95 mediated apoptosis plays an important role in eliminating EBV-immortalized cells, which is counteracted partly by Bcl-2.